The present invention relates to an image processing system which performs projection image distortion correction processing and environmental influence reduction processing, a projector, and an image processing method.
In recent years, a projector has been proposed which corrects distortion of a projection image and reduces environmental influence (e.g. influence of external light or influence of screen color) by projecting an image onto a screen using a projector including a sensor, sensing the projected image using the sensor, and performing image processing.
In a related-art projector, a sensor for correcting distortion of the projection image and a sensor for reducing the environmental influence are separately provided (e.g. “EMP-835” manufactured by Seiko Epson Corporation), or the projection image distortion correction processing and the environmental influence reduction processing are separately performed.
Therefore, a related-art projector takes time for the projection image distortion correction processing and the environmental influence reduction processing.
In order to reduce the time required for such calibration processing, JP-A-2003-339056 reduces the time required for the environmental influence reduction processing by causing a projector to generate visual environment estimation data to reduce the number of times the calibration image is projected.
However, when distortion of the projection image has been corrected, the projection image may not be displayed in the area in which the projection image is originally displayed due to distortion correction. In this case, even if the environmental influence reduction processing is performed by using sensing information of that area, the environmental influence may not be appropriately reduced from the projection image after distortion correction.
For example, JP-A-2004-48694 discloses a projector which determines the visual environment of the projection area based on sensing information of the selected projection area and corrects an image in order to project an image in an area without an obstacle.
However, since the projector disclosed in JP-A-2004-48694 does not include means for determining the position and the shape of the projection image after distortion correction, the environmental influence may not be appropriately reduced.
The position and the shape of the projection image may change due to a zoom function. A projector must appropriately perform the environmental influence reduction processing even in such a case.